1// Copyright 2005, Google Inc. 2// All rights reserved. 3// 4// Redistribution and use in source and binary forms, with or without 5// modification, are permitted provided that the following conditions are 6// met: 7// 8// * Redistributions of source code must retain the above copyright 9// notice, this list of conditions and the following disclaimer. 10// * Redistributions in binary form must reproduce the above 11// copyright notice, this list of conditions and the following disclaimer 12// in the documentation and/or other materials provided with the 13// distribution. 14// * Neither the name of Google Inc. nor the names of its 15// contributors may be used to endorse or promote products derived from 16// this software without specific prior written permission. 17// 18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29// 30// Author: wan@google.com (Zhanyong Wan) 31// 32// The Google C++ Testing Framework (Google Test) 33// 34// This header file defines the Message class. 35// 36// IMPORTANT NOTE: Due to limitation of the C++ language, we have to 37// leave some internal implementation details in this header file. 38// They are clearly marked by comments like this: 39// 40// // INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM. 41// 42// Such code is NOT meant to be used by a user directly, and is subject 43// to CHANGE WITHOUT NOTICE. Therefore DO NOT DEPEND ON IT in a user 44// program! 45 46#ifndef GTEST_INCLUDE_GTEST_GTEST_MESSAGE_H_ 47#define GTEST_INCLUDE_GTEST_GTEST_MESSAGE_H_ 48 49#include <limits> 50 51#include "gtest/internal/gtest-string.h" 52#include "gtest/internal/gtest-internal.h" 53 54namespace testing { 55 56// The Message class works like an ostream repeater. 57// 58// Typical usage: 59// 60// 1. You stream a bunch of values to a Message object. 61// It will remember the text in a stringstream. 62// 2. Then you stream the Message object to an ostream. 63// This causes the text in the Message to be streamed 64// to the ostream. 65// 66// For example; 67// 68// testing::Message foo; 69// foo << 1 << " != " << 2; 70// std::cout << foo; 71// 72// will print "1 != 2". 73// 74// Message is not intended to be inherited from. In particular, its 75// destructor is not virtual. 76// 77// Note that stringstream behaves differently in gcc and in MSVC. You 78// can stream a NULL char pointer to it in the former, but not in the 79// latter (it causes an access violation if you do). The Message 80// class hides this difference by treating a NULL char pointer as 81// "(null)". 82class GTEST_API_ Message { 83 private: 84 // The type of basic IO manipulators (endl, ends, and flush) for 85 // narrow streams. 86 typedef std::ostream& (*BasicNarrowIoManip)(std::ostream&); 87 88 public: 89 // Constructs an empty Message. 90 // We allocate the stringstream separately because otherwise each use of 91 // ASSERT/EXPECT in a procedure adds over 200 bytes to the procedure's 92 // stack frame leading to huge stack frames in some cases; gcc does not reuse 93 // the stack space. 94 Message() : ss_(new ::std::stringstream) { 95 // By default, we want there to be enough precision when printing 96 // a double to a Message. 97 *ss_ << std::setprecision(std::numeric_limits<double>::digits10 + 2); 98 } 99 100 // Copy constructor. 101 Message(const Message& msg) : ss_(new ::std::stringstream) { // NOLINT 102 *ss_ << msg.GetString(); 103 } 104 105 // Constructs a Message from a C-string. 106 explicit Message(const char* str) : ss_(new ::std::stringstream) { 107 *ss_ << str; 108 } 109 110#if GTEST_OS_SYMBIAN 111 // Streams a value (either a pointer or not) to this object. 112 template <typename T> 113 inline Message& operator <<(const T& value) { 114 StreamHelper(typename internal::is_pointer<T>::type(), value); 115 return *this; 116 } 117#else 118 // Streams a non-pointer value to this object. 119 template <typename T> 120 inline Message& operator <<(const T& val) { 121 ::GTestStreamToHelper(ss_.get(), val); 122 return *this; 123 } 124 125 // Streams a pointer value to this object. 126 // 127 // This function is an overload of the previous one. When you 128 // stream a pointer to a Message, this definition will be used as it 129 // is more specialized. (The C++ Standard, section 130 // [temp.func.order].) If you stream a non-pointer, then the 131 // previous definition will be used. 132 // 133 // The reason for this overload is that streaming a NULL pointer to 134 // ostream is undefined behavior. Depending on the compiler, you 135 // may get "0", "(nil)", "(null)", or an access violation. To 136 // ensure consistent result across compilers, we always treat NULL 137 // as "(null)". 138 template <typename T> 139 inline Message& operator <<(T* const& pointer) { // NOLINT 140 if (pointer == NULL) { 141 *ss_ << "(null)"; 142 } else { 143 ::GTestStreamToHelper(ss_.get(), pointer); 144 } 145 return *this; 146 } 147#endif // GTEST_OS_SYMBIAN 148 149 // Since the basic IO manipulators are overloaded for both narrow 150 // and wide streams, we have to provide this specialized definition 151 // of operator <<, even though its body is the same as the 152 // templatized version above. Without this definition, streaming 153 // endl or other basic IO manipulators to Message will confuse the 154 // compiler. 155 Message& operator <<(BasicNarrowIoManip val) { 156 *ss_ << val; 157 return *this; 158 } 159 160 // Instead of 1/0, we want to see true/false for bool values. 161 Message& operator <<(bool b) { 162 return *this << (b ? "true" : "false"); 163 } 164 165 // These two overloads allow streaming a wide C string to a Message 166 // using the UTF-8 encoding. 167 Message& operator <<(const wchar_t* wide_c_str) { 168 return *this << internal::String::ShowWideCString(wide_c_str); 169 } 170 Message& operator <<(wchar_t* wide_c_str) { 171 return *this << internal::String::ShowWideCString(wide_c_str); 172 } 173 174#if GTEST_HAS_STD_WSTRING 175 // Converts the given wide string to a narrow string using the UTF-8 176 // encoding, and streams the result to this Message object. 177 Message& operator <<(const ::std::wstring& wstr); 178#endif // GTEST_HAS_STD_WSTRING 179 180#if GTEST_HAS_GLOBAL_WSTRING 181 // Converts the given wide string to a narrow string using the UTF-8 182 // encoding, and streams the result to this Message object. 183 Message& operator <<(const ::wstring& wstr); 184#endif // GTEST_HAS_GLOBAL_WSTRING 185 186 // Gets the text streamed to this object so far as a String. 187 // Each '\0' character in the buffer is replaced with "\\0". 188 // 189 // INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM. 190 internal::String GetString() const { 191 return internal::StringStreamToString(ss_.get()); 192 } 193 194 private: 195 196#if GTEST_OS_SYMBIAN 197 // These are needed as the Nokia Symbian Compiler cannot decide between 198 // const T& and const T* in a function template. The Nokia compiler _can_ 199 // decide between class template specializations for T and T*, so a 200 // tr1::type_traits-like is_pointer works, and we can overload on that. 201 template <typename T> 202 inline void StreamHelper(internal::true_type /*dummy*/, T* pointer) { 203 if (pointer == NULL) { 204 *ss_ << "(null)"; 205 } else { 206 ::GTestStreamToHelper(ss_.get(), pointer); 207 } 208 } 209 template <typename T> 210 inline void StreamHelper(internal::false_type /*dummy*/, const T& value) { 211 ::GTestStreamToHelper(ss_.get(), value); 212 } 213#endif // GTEST_OS_SYMBIAN 214 215 // We'll hold the text streamed to this object here. 216 const internal::scoped_ptr< ::std::stringstream> ss_; 217 218 // We declare (but don't implement) this to prevent the compiler 219 // from implementing the assignment operator. 220 void operator=(const Message&); 221}; 222 223// Streams a Message to an ostream. 224inline std::ostream& operator <<(std::ostream& os, const Message& sb) { 225 return os << sb.GetString(); 226} 227 228} // namespace testing 229 230#endif // GTEST_INCLUDE_GTEST_GTEST_MESSAGE_H_ 231